Question: What is the value of the following logarithm? $\log_{225} 15$
Solution: If $b^y = x$ , then $\log_{b} x = y$ Notice that $15$ is the square root of $225$ That is, $\sqrt{225} = 225^{1/2} = 15$ Thus, $\log_{225} 15 = \dfrac{1}{2}$.